Michael Cavallari Credit: Grand County Sheriff's Office

Michael Cavallari's death was accidental, a medical examiner has ruled, saying that Kristin Cavallari's brother died of hypothermia after he crashed his car in Utah back in December.

As Us Weekly reported previously, Michael was exposed to cold temperatures before he died in Salt Wash, Utah. His body was discovered on Thursday, December 10, at approximately 10:30 a.m. local time, in what Grand County Sheriff Steven White described as a "steep and very rocky area.”

And on Tuesday, February 9, Grand County sheriff officials confirmed via a news release that the frigid temperatures which led to hypothermia after the crash was his official cause of death.

White told ABC News on Tuesday that they were still waiting on toxicology reports to find out if Michael had any drugs in his system. White said the autopsy report closes the case, but questions may forever linger about what exactly happened.

White also revealed that Michael's family had been informed of the findings earlier in the week. Kristin, who wrote an emotional tribute to her beloved brother via Instagram in the days that followed his passing, has yet to respond.

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